The most recent incidents were during a period of high fire danger on Sunday in San Ramon and Monday in Las Trampas Regional Wilderness. The first fire burned 7 acres and injured one firefighter. The second fire burned 6 acres near that same location.
RELATED: Vegetation fire in San Ramon prompts evacuations
Investigators working with the San Ramon Police Department identified 39-year-old William Priest at his home Monday evening. He's been booked into county jail on $75,000 bail.
Another suspect who has not been identified was arrested in two previous arson wildfires, according to the San Ramon Valley Fire Protection District.
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A two-alarm fire burned 4 acres and threatened homes in Danville on Aug. 28. One firefighter was injured, and Danville police arrested a suspect on suspicion of recklessly starting that fire. Two weeks later, that suspect was arrested a second time for starting a fire in the Blackhawk area on Sept. 16.
San Ramon Valley Fire on scene working hard to extinguish the fire, which is dangerously close to residences. pic.twitter.com/oQfFn5fvPN— San Ramon Police (@sanramonpolice) September 24, 2018
View of yesterday’s burn zone on far left and today’s fire on right.— Captain Denton Carlson (@SRPDCarlson) September 24, 2018
If you saw anything unusual in this area yesterday or today, please call us at 925-973-2779. pic.twitter.com/KiW6VSnQqQ
Another activation vegetation fire near Crow Canyon and Bollinger Canyon Roads. @srvfpd personnel already on scene. Farther up the hill today and roughly 100 yards from @CityofSanRamon residences. pic.twitter.com/mIJq9jyah6— Captain Denton Carlson (@SRPDCarlson) September 24, 2018
Yesterday's fire came way too close to @CityofSanRamon homes. Thanks to quick work by @srvfpd, no homes were damaged!👏👍👏— Captain Denton Carlson (@SRPDCarlson) September 24, 2018
Please be extra careful over the next few days...@NWSBayArea has issued a RED FLAG warning for the east bay hills through 5pm tomorrow. #nofires pic.twitter.com/lCHsyVtEqF
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